From Draft No. 4: On the Writing Process:
I have often heard writers say that you have written your lead you have in a sense written half of your story. Finding a good lead can require that much time, anyway–through trial and error. You can start almost anywhere. Several possibilities will occur to you. Which one are you going to choose? It is easier to say what not to choose. A lead should not be cheap, flashy, meretricious, blaring. After a tremendous fanfare of verbal trumpets, a mouse comes out of a hole blinking. . . .
The lead–like the title–should be a flashlight that shines down into the story.
(p. 50).